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Crypto++® Library 5.6.5

Crypto++ Library is a free C++ class library of cryptographic schemes. The library contains the following algorithms:

Algorithm Name
authenticated encryption schemes GCM, CCM, EAX
high speed stream ciphers ChaCha (ChaCha8/12/20), Panama, Sosemanuk, Salsa20, XSalsa20
AES and AES candidates AES (Rijndael), RC6, MARS, Twofish, Serpent, CAST-256
other block ciphers IDEA, Triple-DES (DES-EDE2 and DES-EDE3), Camellia, SEED, RC5, Blowfish, TEA, XTEA, Skipjack, SHACAL-2
block cipher modes of operation ECB, CBC, CBC ciphertext stealing (CTS), CFB, OFB, counter mode (CTR)
message authentication codes VMAC, HMAC, GMAC (GCM), CMAC, CBC-MAC, DMAC, Two-Track-MAC, BLAKE2 (BLAKE2b, BLAKE2s), Poly1305, SipHash
hash functions BLAKE2 (BLAKE2b, BLAKE2s), Keccack (F1600), SHA-1, SHA-2, SHA-3, Tiger, WHIRLPOOL, RIPEMD-128, RIPEMD-256, RIPEMD-160, RIPEMD-320
public-key cryptography RSA, DSA, Determinsitic DSA, ElGamal, Nyberg-Rueppel (NR), Rabin-Williams (RW), EC-based German Digital Signature (ECGDSA), LUC, LUCELG, DLIES (variants of DHAES), ESIGN
padding schemes for public-key systems PKCS#1 v2.0, OAEP, PSS, PSSR, IEEE P1363 EMSA2 and EMSA5
key agreement schemes Diffie-Hellman (DH), Unified Diffie-Hellman (DH2), Menezes-Qu-Vanstone (MQV), Hashed MQV (HMQV), Fully Hashed MQV (FHMQV), LUCDIF, XTR-DH
elliptic curve cryptography ECDSA, Determinsitic ECDSA, ECGDSA, ECNR, ECIES, ECDH, ECMQV
insecure or obsolescent algorithms retained for backwards compatibility and historical value MD2, MD4, MD5, Panama Hash, DES, ARC4, SEAL 3.0, WAKE-OFB, DESX (DES-XEX3), RC2, SAFER, 3-WAY, GOST, SHARK, CAST-128, Square

Other features include:


Crypto++ Library is copyrighted as a compilation and (as of version 5.6.2) licensed under the Boost Software License 1.0, while the individual files in the compilation are all public domain.


The current version of Crypto++ supports the following compilers:

For detailed build status and notes on various compiler/OS/CPU combinations as well as information about compiling earlier versions of Crypto++, please see this wiki entry.

What's new?


The downloads for the most recent Crypto++ 5.6 libraries are below. If you need older downloads, from Crypto++ 5.5 to Crypto++ 2.3, then visit the Downloads page. The Downloads page provides checksums for all releases hosted on the website.

Release Date
US Original
Release Notes
(with Hashes)
GitHub Mirror
2016-10-11 Crypto++ 5.6.5 5.6.5 Release Crypto++ 5.6.5 Crypto++ 5.6.5
2016-09-11 Crypto++ 5.6.4 5.6.4 Release Crypto++ 5.6.4 Crypto++ 5.6.4
2015-11-20 Crypto++ 5.6.3 5.6.3 Release Crypto++ 5.6.3 Crypto++ 5.6.3
2013-02-20 Crypto++ 5.6.2 5.6.2 Release Crypto++ 5.6.2 Crypto++ 5.6.2
2010-08-10 Crypto++ 5.6.1 5.6.1 Release Crypto++ 5.6.1 Crypto++ 5.6.1
2009-03-27 Crypto++ 5.6.0 5.6.0 Release Crypto++ 5.6.0 Crypto++ 5.6.0

Remember to use the "-a" auto-convert text files option when unzipping on a Unix machine. After downloading, please read the Readme.txt included in the zip archive for build instructions and other important notes.

While You Are Downloading

FIPS 140-2 Validation

The following versions of Crypto++ have been validated by NIST and CSE for FIPS 140-2 level 1 conformance. Because only compiled executable code can receive FIPS validation, these versions are listed separately from the other source-code-only downloads. These download packages include the validated binary object, header files, API reference, and FIPS related documentation. Source code is also included for debugging purposes. (You cannot compile Crypto++ yourself and claim FIPS 140-2 conformance on the resulting module, unless the it goes through the validation process again.)

Because these packages contain compiled executable code, they have been signed with a PGP public key which is included inside the package. You can verify the PGP key's fingerprint by following the certificate link and obtaining a copy of the Crypto++ Library Security Policy from NIST's web site. The fingerprint is given in the Security Policy.

Mailing Lists

There are two mailing lists for Crypto++. The first is, and the second is

As a courtesy, please join the discussion list with your real name instead of an online handle. Alternate webviews are for the lists are available at Crypto++ Announce - Google Groups and Crypto++ Users - Google Groups.

When posting a question to the Crypto++ user mailing list, please provide the following information, if applicable:

Source Code and Contributions

The source code and its planned changes are available at the following locations.

Contributions of all types are welcomed. Contributions include the following.

If you think you have found a bug in the library, then you should discuss it on the Users mailing list. Discussing it will help bring the issue to the attention of folks who can help resolve the issue. If you want to contribute a bug fix to the library, then make a Pull Request or make a Diff available somewhere. Also see Bug Reports on the wiki.

Features and enhancements are welcomend additions to the library. This category tends to be time consuming because algorithms and their test cases need to be reviewed and merged. Please be mindful of the test cases, and attempt to procure them from an independent source.

The library cherishes test scripts and test cases. They ensure the library is fit and they help uncover issues with the library before users experience them. If you have some time, then write some test cases, especially the ones that are intended to break things.

Branch and release testing is your chance to ensure Master (and planned merges) meets your expectations and perform as expected. If you have a few spare cycles, then please test Master on your favorite platform. We need more testing on MinGW, Windows Phone, Windows Store, Solaris 10 (and below), and modern iOS and OS X (including TV and Watch builds).

Documentation and updates includes both the inline source code annotations using Doxygen, and the online information provided in the wiki. The wiki is more verbose and usually provides more contextual information than the API reference. Besides testing, documentation is one of the highest returns on investment.

If you are interested in paid support for Crypto++ or consulting on a Crypto++ related project, then please see this list of companies and individuals providing services on the wiki. This listing is a free service for the Crypto++ community, and anyone may sign up to be listed by creating an account on the wiki.

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Originally written by Wei Dai Last modified: Jan 31, 2017 Currently maintained by Jeffrey Walton
and the Crypto++ community